The application of certain cosmetic or medicinal liquids to the entire body or a major portion thereof, can be facilitated by mixing them with shower water. A convenient procedure is to mix the additive or bathing liquid into the shower water only at a particular time such as the end of the shower, and to then mix only a small predetermined amount of the liquid, to avoid wasteage.
In order to enhance the convenience of the dispensing apparatus, it is desirable that a minimum of maintenance be required by the user, in measuring out and refilling the dispensing reservoir. Also, in many situations it is desirable to enable the user to select which of a plurality of different bathing liquids to apply. It is also desirable to construct the coupling apparatus which mixes the shower water with the bathing liquid, so that it operates with safeguards against the retention of stale water between shower usages, the backflow of water into the home shower system, and the backflow of shower water into the bathing liquid container and dispensing apparatus. All of this is preferably accomplished in a system of simple design to enable its manufacture and installation at low cost and to assure reliable operation.